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Copyrolysis of two waste wood samples with block polypropylene were investigated for the reaction characteristics and properties of the pyrolytic oil. The thermal decomposition of the mixture led to an increase in the temperature range for the decomposition of polypropylene, which implied an interaction in the mixture. New tar compounds were also identified from the copyrolysis using pyrolysis gas chromatography/mass spectrometry. The oil produced from the mixtures in a batch type reactor had an increase in the mass yield, with higher C and H, and lower moisture contents. [ABSTRACT FROM AUTHOR]

Providencia alcalifaciensis a member of the Enterobacteriaceae family that occasionally causes diarrheagenic illness in humans via the intake of contaminated foods. Despite the epidemiological importance ofP. alcalifaciens, little is known about its pathobiology. Here we report thatP. alcalifacienscauses barrier dysfunction in Caco-2 cell monolayers and induces apoptosis in calf pulmonary artery endothelial cells.P. alcalifaciensinfection caused a 30% reduction in transepithelial resistance in Caco-2 cell monolayers, which was greater than that for cells infected withShigella flexnerior non-pathogenicEscherichia coli. As with viable bacteria, bacterial lysates treated with heat, benzonase or proteinase, but not with polymixin B, were also involved in the cellular response. TLR4 antibody neutralisation significantly restored theP. alcalifaciens-induced transepithelial resistance reduction in Caco-2 cells, suggesting that lipopolysaccharides (LPSs) might play a central role in this cellular response. Western blotting further indicated thatP. alcalifaciensLPSs reduced occludin levels, whereas LPSs fromShigellaorE. colidid not. Although the viability of Caco-2 cells was not altered significantly, the calf pulmonary artery endothelial cell line was highly sensitive toP. alcalifaciensinfection. This sensitivity was indeed dependent on LPS, which induced rapid apoptosis. Together, these data show thatP. alcalifaciensLPSs participate in epithelial barrier dysfunction and endothelial apoptosis. The findings give insight into the LPS-dependent cell signal events affecting diarrheagenicity during infection withP. alcalifaciens. [ABSTRACT FROM PUBLISHER]

As the shipbuilding industry expands, accurate and efficient planning and scheduling of the production process is becoming increasingly important and complex. The availability of space and load in workshops should thus be examined in scheduling the production process. The variety of material, facilities, and information resources makes the spatial planning difficult. In the present work, a spatial planning and scheduling system is developed to support spatial planning and scheduling in block assembly shops, and the workload balance of workshops. The requirements and functions of the system are described and functional components are designed and implemented, based on an object-oriented methodology. The integrated environment is presented in this paper. This system can be expanded to any workshop that requires spatial planning and scheduling. [ABSTRACT FROM AUTHOR]

An unusually thick and soft clay, which is called Busan clay, has been deposited throughout the Nakdong River estuary, South Korea. Although many reclamation works have been carried out in the area since early 1990s, large- and small-scale slope failures have taken place mostly during the soil placement on the clay. A case history briefly describes failure of a breakwater resulting from overestimation of the undrained strength, obtained from laboratory testing. An attempt has been made to examine the methods for determining the undrained strength from field vane testing. For this, the undrained strengths from field vane testing were obtained using different correction factors and compared with each other at five sites in the area. An alternative correction method applicable especially for Busan clay was found, using a range of corrected strength ratios. Further, relationships between the depositional environment and the undrained strength of the clay have also been investigated. [ABSTRACT FROM AUTHOR]

Despite a number of geotechnical investigations that have been carried out in the Busan new port area of South Korea, the local practicing engineers have been unable to deduce successfully the geotechnical properties of the clays due to their spatial variation. In the area, clay deposits, so-called Pusan clays, are unusually thick, varying from 20 m to 70 m in thickness. For this study, comprehensive geological and geotechnical investigations were carried out with sophisticated sampling techniques, in situ and laboratory tests as well as geological analyses at an additional three locations. As a result of the investigations, it was found that depositional environments are closely related to the relative changes in sea level and have different features depending on location and depth. The clays consist of soft and stiff clays in the upper and the lower layers, respectively, which are classified as normally consolidated and cemented clay. Moreover, most of the geotechnical properties undergo small changes due to their depositional environment. Information about these effects would be quite helpful to understand the spatial variation of geotechnical properties as well as the effect of sample disturbance. Some correlations which reflect the geological history of the deposts were conducted for physical indexes and mechanical properties. [ABSTRACT FROM AUTHOR]

In a mass burn waste incinerator, the waste undergoes combustion in the bed on the grate and the products of incomplete combustion are destroyed in the gas plenum above the bed. Thus, it is essential to consider the reaction in both the waste bed and the gas plenum when evaluating the combustion performance using computational fluid dynamics (CFD). However, solving the two-phase reacting bed of waste is not straightforward in CFD simulations. This paper presents the combustion and gas flow of a waste incinerator using a new simulation approach that incorporates two models: FLIC for the reacting bed of solid fuels and FLUENT for the turbulent reacting flow of the gas plenum. The two models were linked through the boundary conditions on the waste bed in such a manner that FLIC provides the gas properties leaving the bed as an inlet condition of the gas flow and FLUENT produces the radiation transferred to the bed. The predicted results were compared with on-site measurements in the plant by a novel instrument that collected the temperature, oxygen concentration, and motion data while tumbling with the waste particles within the bed. The measured data were highly fluctuating, but FLIC satisfactorily predicted the overall trend of temperature and oxygen concentration including the upper and lower boundaries of the violent fluctuations. The FLIC/FLUENT combined simulation provided crucial information on the nature of combustion and flow characteristics such as the ignition and burnout points of waste, the rates of each combustion process, and the subsequent gas flow pattern in the combustion chamber. [ABSTRACT FROM AUTHOR]

The effects of cross-linking and crystallinity on the aging of plasma-treated high-density polyethylene (HDPE) have been investigated. In the case of mixed argon and oxygen, aging has been found to be reduced with an increased amount of argon in the mixture owing to an increased degree of cross-linking. A similar decrease in hydrophobic recovery has been achieved by increasing the crystallinity of HDPE. Diffusion of polar functional groups from the surface into the bulk has been observed to be lowered by both increasing the degree of cross-linking and crystallinity. The samples were analyzed by angle-resolved XPS, contact angle measurements and SEM investigations. [ABSTRACT FROM AUTHOR]

To improve the hydrophilicity and reduce the aging effect, argon and oxygen mixtures were employed in the plasma treatment of low-density polyethylene (LDPE). Argon resulted in producing more oxygen ions and radicals in the plasma than only oxygen and forming cross-linked layers on the LDPE surface. Therefore, the water contact angle on plasma-treated LDPE decreased and the oxygen content measured by X-ray photoelectron spectroscopy (XPS) increased with the increase of argon content. The aging effect was also much reduced with the increase of argon content since argon induced cross-linking. [ABSTRACT FROM AUTHOR]